Telephone



2 Sheets- Sheet 1.

Patented Jan. 3, 1888.

(No Model.)

V. M. BERTHOLD.

TELEPHONE.

ENO. 375,862.

(No Model.) 2 Sheets-'Sheet 2. V. M. BERTI-IOLD.

TELEPHONE.

No. 376,862K -Patented Jan. 3, 1888.

Witwse/s,

UNITED STATES PATENT OFFICE@ Y V. MAXIMILIAN BERTHOLD, OF CAMBRIDGE, ASSIGNOR TO THE AMERICAN BELL TELEPHONE COMPANY, OF BOSTON, MASSACHUSETTS.

TELEPHONE.

SFECIEICATION torn-zin. part of Letters Patent No. 375,852, dated January 3, 1888.

(No model.)

To all zotom'z't may concern:

Be it known that I, V. hLrxnuILLrN-BER` THOLD, of Cambridge, county of Middlesex, State of Massachusetts, have invented an lmprovemcnt in Telephones, of which the following description, in connection with the accompanying drawings, is a specification, like letters on the drawings representing like parts.

My invention relates to telephones ofthe class t@ commonly known as transmitters or batterytelephones,in which theelectricimpulses are produced by varying the resistance of a battery-current in accordance with the soundwaves that commonly act on a diaphragm or vibrator, which in turn acts on electrodes in the battery-circuit to vary the resistance in said circuit at the contact-point of said electrodes.

The present invention refers especially to the construction of the battery and its arrange ment with relation to the other elements of the apparatus, some of the objects of the inventien being to produce a more compact and portable instrument than those heretofore made and to reduce the cost of the apparatus and facilitate the exchange of batteries or the replacing of an exhausted battery by a fresh one.

A small portable battery-telephone or transmitter such as produced by this invention isA of great value for outof-door work or for a iield-telephonefor instance, for military purposes, or where the telephone has to be carried about from place to place. Attempts have been made to use the hand magneto-telephone for such purposes, but the results are unsatisfactory, and a batterytelephone capable of producing a considerable currentris much desired for such uses. Y

The instrument forming the subject of this invention is also of great value for private installations-as, for example, for communication in large hotels or other large buildings and on vessels. The battery is so constructed and arranged as to render it difficult for a subscriber of a telephone exchange to tamper with or injure it.

The invention maybe embodied in a telephone having the general construction of the 5o well-known Blake transmitter, so far as relates to the microphone contact or electrodes that vary the resistance of the battery-current, or any other suitable microphone may be used; but, instead of using a separate batt-ery outside the ease that contains the microphonecontact and induction coil, the said battery is,

in accordance with this invention, introduced into the said case and made constructively a part ot' the telephone itself, the said battery or a portion thereof forming a portion of the 6o soundchamber,and in some cases constituting the vibrator that acts on the electrodes or microphone-contact. A

My invention is, however, not limited to any one special type of battery, and I have shown 55 several kinds-as, for example, a dry, a moist, and a liquid battery, each of which will operate effectively, and each of which has some special advantage for some of the purposes to which the telephone may be put. 7o

The invention consists partly in a telephone having a galvanic batterylocated between the mouth-piece or sound-opening andthe micro phonecontact and partly in various details of construction of the battery and of the box or case in which it is used, in combination with the microphonecontact, by which ready access may be had tothe battery without disturbing the adjustment of the microphone, and a battery may be readily removed and re- 8o placed by a new one when required.

Figure 1 is a sectional view of a battery-telephone or mierophone-transmitter embodying this invention and containing a moist battery; Fig. 2, an elevation of the parts connected with the door or front of the telephone box or case as seen when looking toward the inside of the boxdoor; Fig. 3, a sectional detail showing the main parts of a telephone embodying this invention having a dry battery; Fig. 4, a sec- 9o tional view of a telephone embodying this invention havinga liquid battery; Figs. 5 and 6, sectional views showing a modified arrangement which may be desirable with a liquid battery; and Figs. 7 to 15, inclusive, details 95 showing the construction ofthe different kinds of batteries.

The telephone comprises the usual electrodes or microphone-contact, a b, which may be of the same construction as in the well-known 1ro Blake transmitter, or may be of any other suitable or usual constructionas, for example, the one shown in Fig. 6, in which the electrode a is composed of a mass of finelydivided conducting material-for instance, powdered carbon. The said electrodes are preferably contained in a box or case, c, (shown in Fig. 1,) substantially of the same construction as commonly employed for the Blake trans mittcr,saidbox havingamouth-piece or soundopening, c', and containing an induction-coil, d, the primarycoil of which is connected with the electrodes a b, while the secondary coil is connected with the line over which the communication is to be transmitted.

Instead of having the battery B, the c .rrent of 'which is controlled by the resistance at the electrodes a b in a separate case, and haring no constructive relation with themouth-piece and microphonecontact, as has been heretofore usually practiced, the said battery is in accordance with this invention constructed to be contained within the transmitter box or case c and to enter into constructive relation with the other parts of thetelephone, being, as herein shown, interposed between the mouthpiece c', at which the sound-waves enter, and the microphonecontaets c b.

Batteries of various construction may be used in ,carrying out this invention, which batteries form a whole or a part of the soundchamber and vibrator that is set in operation by the sound-waves, and in turn operates upon the microphonecontact c b to vary the resistance to the current of the said battery B.

The forni of battery represented in Fig. l and in detail in Figs. 7 to 10, inclusive, is well adapted for use in a telephone of this kind, as it gives out no perceptible gases or disagreeable odors, and, in order to guard against any corrosion of the metallic parts of the microphone proper, such parts are coated with shellac or varnish. This battery may be ofthe same nature as the well-known Niaudet battery,which is fully described in tlieFTtait Elementaire de la Pile Electrique, by Ch. Niaudt, published in Paris, 1885. This battery comprises a box, e, made of zinc, one side of which is composed of a plate, e, (see Fig. 7,) of about the size ofthe usual microphone-diaphragm, having a central opening, et, and having around its outer edge a rim or fiange, e3, and around the edge of the opening ci asecond flange, 6*, which does not project quite so far vfrom the face of the plate as does the flange e3.

(See Fig. l0.) Vithin this box are placed several pieces or disks, e5, (see Fig. 8,) of porous material-such, for example, as blottingpaper or felthavng central openings tightly fitting over the flange or tube e'L at the middle of the box. The tube or flange e is insulated in any suitable manner, as by wrapping around it paper saturated with parafne or oil. The porous material,e5,is saturated in a solution of kcommon salt (chloride of sodium) and placed in contact with the inner face of the disk e. On these disks e5, of porous material, is placed an annular carbon disk, e6, Fig. 9, which is pressed tightly against the saturated disks e5,

but is insulated from the zinc flanges e3 @Sand upon the other-side of the carbon disk is laid another disk, c7, of porous material, and upon that a mass, es, Fig. l0, of mica chips or shavings, which are madev into paste by pouring overthem asolution of calcium chloride, which is quickly absorbed. On this layer of mica shavings is placed an annular disk, e, of oiled silk, which prevents access of air to the various disks in the box. These various disks are shown separate from one another in Fig. 10, in proper relation to one another to enter the box c, and when all are pressed into the box the surface of the disk e, of oiled silk, is about flush with the edge of the flange et, as shown in Fig. 1, and the battery proper is then complete, the box itself constituting one clement of the battery and the carbon disk e constituting the other element,and having connected with it in any suitable manner a wire or conductor, 2, which passes out through the oiled silk without making electrical contact with the zine box. A diaphragm or plate, e, of any suitable material-such, for example, as mica-of the saine diameter as the plate e', but having no central opening, is then fastened in any suitable manner on the edge ot' the flange e3, that forms the cylindrical side of the box, and is heldin place by an annular ring or collar, cl3, which is preferably also made of zinc and fitted tightly over the flange e3. The diaphragm e12 is thus supported at a short distance from the disk of oiled silk, so as to form a sound-chamber, i', (see Fig. 1,) of about the same dimensions as commonly used in the Blake transmitter. One or more pieces of rubber may be placed between the diaphragm e and oiled silk, as shown at e, to insure that the diaphragm shall beproperlyseparated from the oiledsilk disk e9 to maintain the sound-chamber in proper condition, which sound chamber communicates through the openiuge2 in the zinc plate and the tube formed by the tiange e* around saidopening with thc mouth-piece c,at which the sound-waves enter, the said sound-waves thus passing wholly through the battery and entering between one side of the battery and the diaphragm supported at a short distance therefrom, and the said diaphragm operating upon the electrodes a b in substantially the usual manner.

The elements of the battery may be treated in any suitable way to produce greater efficiency-as, for example, by coating the inner surface of the zinc box with a mixture ot' tal- ]ow, parafine, and mercury, and by treating the carbon with a sugar solution and heating in a smoky flame, and by varnishing the outside of the box, excepting the cover el.

In order to facilitate the introduction of the battery to its working position, the usual door or cover, c, of the telephone-case c, which is hinged to open in the usual manner, (see Fig. 2,) is provided at its inside with a plate, c, which may be ot' wood and about the thickness of the battery B, constructed as described, and the said plate cs is preferably connected at its IIO upper end, by hinges et, with the door c, and provided at its lower end with a suitablefastening, (shown as a spring-catch, 05,) to retain it fastened down against the inner face of the door c2. The said plate c has a circular opening of proper size to receive the battery B within it, and by merely unfastening the catch c5 and turning the plate c3 up on its hinges the battery may be inserted in or removed from the opening in the said plate from the side opposite the electrodes c b, which thus do not need to be disturbed by the act of taking out 0r putting'in a battery.

The plate ci' may have one or more springarms, c, (see Fig. 2,) that engage the inner part of the battery and hold it against the in- ,ner face of the door c2 when the plate c3 is turned down and fastened in its normal position. One or more of said spring-arms may bear againstthe diaph ragni to act as a damper in the usual manner. One of the said springarms ci makes electric contact with the box which forms the zinc element of the battery, and said spring is connected, by a wire, 3, with the electrode tt of the microphonecontact, from which the current will pass by conduction to the electrode b and metallic frame-work b',

that supports it, from which the circuit is continued by a suit-able conductor, a, to one of the hinges c4 of the plate c, and thence by a conductor, 5, to one of the hinges of the door ci, connected in the usual manner with one terminal ofthe primary coil of theinductioncoil d, the other terminal of which is connected with the other hinge ot the cover' c, from which the circuit is continued by wire 6 to the other hinge of the plate c3, which is connected, by wire 7,with the binding-post 8,which receives the wire 2, that passes to the carbon element e of the battery, and thus completes the circuit of the battery through the microphone-contact land induction-coil by merely placing the battery in position and connecting.)r the wire 2 with the binding-post 8.

A battery of this kind produces a suitable current for telephonie transmission, and will retain its activity for aconsiderable time, and, being very small, compact, inexpensive, and easily placed in operative connection with the other parts of the telephone, its use greatly facilitates the proper maintenance of the apparatus, as an operator can easily take a large number of such batteries and substitute them f'or the exhausted batteries.

The entire apparatus can thus be made in a very compact form, well adapted for use in a portable instrument whenever required, because the entire essential parts, including the battery, may be placed in smaller compass than the usual Blake transmitter, without its accompanying battery, which, as commonly used, is considerably larger than the transmitter itself.

For a portable instrument the smaller battery (represented in Fig. 3 and in detail in Figs. 12 to 15) may be found more convenient. This battery may be composed of a disk of zinc, g, nearly the size of the usual diaphragm, and a plate of silver, g', separated byone or more sheets, g2, of porous material-such, for example, as blotting-paper saturated with ammonium chloride or sulphate of zincand placed in contact with the said zinc disk. The plate or sheet, g', of silver is preferably of a little smaller diameter than the zinc disk. It has a projecting strip or tongue, g3, at one side, preferably about one inch long. Upon one side of this silver plate is laid a paste of silver chloride, or the chloride may be melted upon the plate. The silver disk thus prepared is then pressed firmly upon the saturated por-v ous material, g2. (See Fig. 15.) The opposite side of the silver plate is preferably strength cned by a disk, g4, which may be of mica and of the same size as the zinc plate g, and is provided with a notch, g5, which is placed opposite the tongue g3 ofthe silver plate, which is folded down in said notch onto the face of the mica plate. The zine, silver, and mica plates, with the saturated porous material between them, are then fastened together by a rubber band, g, stretched over the edge, as best shown in Fig. 3, and the silver stem g is then folded over the rubber band and constitutes one of the poles of the battery. This battery is then placed in the iron seat h (see Fig. 3) used in the Blake transmitter in place of the usual iron diaphragm, so that the mica plate lies at the front opposite the mouth-piece c2 and the zinc plate opposite the electrode a, the said zinc plate being provided with insulating material-such, for example, as a small piece of mica, c7-to preventmaking electrical contact with the said electrode a. The silver tongue y thus makes automatic contactwith the iron frame, which carries the current to the electrede bin the usual manner, from which the circuit is continued to the electrode a., connected through one hinge of the box, with one terminal of the primary inductioircoil, the other terminal of which is connected with the other hingeof the box, from which the circuit is completed by a conductor fastened to the zinc plateg of the battery. In this connection between the hinge and zinc plate a binding-post may be used connected with the hinge of the box and adapted to receive the wire soldered to the zinc plate, so that the connection may be readily made when the battery is inserted in its place in the frame. This battery may be inserted or removed in exactly the same manner as the usual diaphragm in the Blake transmitter, and in this construction the entire battery forms one side of the soundecharnbcr i', which is included between it and the inner face of the box-door c2, and the entire battery also forms the diaphraghm or vibrator that is set in lnotion by the sound-waves, and acts on the 'electrodes a o to vary the resistance, thereby controlling the current generated within it.

A battery of this construction is of high power in proportion to its size and of considerable permanence in action. It is very light IXO Fig. 4.

and durable and may be used for a variety of purposes.

In case it is desirable to use a large liquid battery, giving greater volume of current, I adopt the constructions represented in Figs. 4, 5, and 6. t

In the construction represented in Fig. 4, the inclosing case or receptacle ofthe battery constitutes one elementthereo'i", and is constructed very much like that represented in Fig. l, having an end plate, e, with a central opening, e, and a cylindrical Harige or tube, eti, around the outer edge ofthe said plate, and a tube, e, around the edge of the said opening, but much longer than the flanges e3 e of the battery represented in Fig. l. The tube e is shorter than the outer cylinder, e, and the space between the said tube and cylinder is closed by a second disk, c25, which may be soldered upon said tube and cylinder, so as to form a tight annular or cylindrical reservoir of considerable capacity. The said reservoir contains an annular carbon element, e, which is prevented from coming in contact with the reservoir by disks e, of insulating materialsuch, for instance, as paper or oiled silk. rIhe space between the inner surface ofthe carbon et and the tube eIAL is lled with loose asbestus saturated witha solution of chloride of lime, as represented at e, and the space around the carbon and within the cylinder ez3 is filled with mica shavings saturated with a solution of common salt, (chloride of sodimm) as indicated at e. The diaphragm e32 is then fastened upon the end of the cylinder @23, being held in place by a ring, es, that tits over the said cylinder e.

The battery is held in the transmitter-case between the mouth-piece c and electrodes a b by a hinged plate, ci", connected with the door c of the box by hinges in subsfantiallythe same manner as the plate c3, described in connection with Fig. l; bnt,owing to the greater length of the battery,the diaphragm end is supported in a second frame, ci, which also supports the electrodes a b and their adjusting devices, and is connected withthe plate c3 by posts 032. The connecting-wire e from the carbon element e'zpasses through an insulating-plug, e", in the cover c25 ot' the battery-receptacle and the connections with the electrodes a b, and the iu duction-coil may be made as described in connection with Fig. 2.

The battery just described is practically a liquid battery, although the liquid is partially iilled with the absorbent material around the carbon cylinder.

, In some cases it may be desirable to use a battery of similar construction to that last described, but with the cylinder in a vertical instead of horizontal position. In such cases the construction represented inv Figs. 5 and 6 may be adopted, the battery being substantially the same as described in connection with In this construction the bottom m and rear part, m', of the inclosing-case are fastened together permanently, and the top m2 and front m3 of the case are also fastened together permanently, butdetachable from the bottom and rear. The sides of the box may be connected either with the stationary part m m or the removable part m2 m3, as may be desired. The battery sets on the bottom m, which is provided with a mouth-piece, c', that curves upward to enter thc tube et of the battery, so that thesonnd passes through the battery to the sound-chamber t, formed between the cover e and diaphragm ci at the upper end of the battery, which is held in the frame c, that supports the electrodes a b, and is connected with posts c, that are fastened in'sockets c43 on the hase a of the box, being held in said sockets by suitable clamping devices, (shown as setscrews,) so that said posts may be readily unfastened and the frame with the electrodes lifted off from the base, so that thebat tcry may be removed. In this construction a liquid battery may be usedwithout absorbent material in the liquid, if desired, and, instead of zinc and carbon for the elements, iron and zinc may beused, the box being composed of iron in the same shape as the box or cylindrical receptacle described, and the zinc being in the saine shape and location as the carbon. Vith these elements hydrate of potash and copper oxide may be used in the exciting and dcpolarizing liquids.

The construction represented in Fig. 6 is substantially like that represented in Fig. 5, but shows the invention embodied in a transmitter having powdered carbon for one of the electrodes, a, the said carbon being contained in a cylindrical receptacle on the diaphragm. An adjusting-screw, b5, is used to sustain the weight ofthe electrode b.

I have not attempted to mention or describe particularly all the types of battery or forms of microphonecontact that might be used in carrying out my invention, as it is obvious that a very great variety might be used, lnany of which will be readilysuggested to those familiar with such apparatus; but the forms illustrated and described show practical means for embodying' my invention, which consists, generally, in making a battery of small size, so that it can be placed in a transmitter-box without materially enlarging the same, and in locating the battery between the mouth-piece or sound-opening and the microphone-contact, and using asa vibrator or sound-col lector a diaphragm connected with and forming, constructively, a part of the battery, and more specifically in providing the battery with a tubular passage, through which the soundwaves pass, and in various devices for holding the battery and making the electrical connections therefrom.

I claiml. The combination of the microphone or variable-resistance electrodes of a batterytelephone with a battery located between the said electrodes and the mouth-piece or sound-openv ing of the instrument, and having connected with it a sound-collecting plate or diaphragm IOO IIO

that aotuates the said electrodes, substantially as described.

2. A galvanic battery having a passage through it for soundwaves and a vibrator or sound-collector, combined with elect rodes connected with the poles of said battery and operated by said vibrator, substantially as described.

3. A battery for a telephone-transmitter, comprising a ease or box constituting one element of the said battery, and a co-operating element inclosed in the said case or box, and a vibrator or diaphragm connected with the said case or box and forming therewith a sound-chamber, substantially as described.

4. A battery for a telephonetransmitter,

comprising a plate having a central opening and rims or iianges surrounding said plate and opening, the said parts forming one element of the battery and containing the other element and exciting material for the battery, the said central opening and ange surrounding it constituting a passage for the sound-waves, substantially as described.

5. The combination of a galvanie battery having a vibrator or diaphragm connected with it, and an inelosing-case for said battery and the cooperating electrodes and inductioncoil, and a movable plate or frame within said case supporting the said electrodes and holding the battery in proper position with relation thereto, by means of which frame the bat- Y tery may be changed Without disturbing the adjustment of the electrodes, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing Witnesses.

V. M. BERTHOLD.

Vitnesses:

Jos. P. LIvERMoRE, JAS. J. MALONEY. 

